ALS31000 and A31004: Unidirectional Linear Hall-Effect Sensor IC with Analog Output, in Miniature Low-Profile Surface-Mount Package

New applications for linear output Hall-effect sensors, such as displacement and angular position, require higher accuracy and smaller package sizes. The Allegro ALS31000 and A31004 linear Hall-Effect sensor ICs have been designed specifically to meet both requirements.

The accuracy of these devices are enhanced via end-of-line optimization. The ALS31000 and A31004 feature non-volatile memory to optimize device sensitivity and the quiescent voltage output (QVO: output in the absence of a magnetic field) for a given application or circuit. Optimized performance is sustained across the full operating temperature range by programming the temperature coefficient for both sensitivity and QVO at Allegro end-of-line test.

These ratiometric Hall-effect sensor ICs provide a voltage output proportional to the applied magnetic field. For the ALS31000, the quiescent voltage output is adjusted to around 0.7 V and the output sensitivity is set to 2.4 mV/G, while the A31004 quiescent voltage output is adjusted to around 0.5 V and the output sensitivity is set to 3.3 mV/G.

The features of these linear devices make them ideal for use in automotive and industrial applications requiring high accuracy and operation across an extended temperature range, –40°C to 150°C.

Each BiCMOS monolithic circuit integrates: a Hall element, temperature-compensating circuitry to reduce the intrinsic sensitivity drift of the Hall element, a small-signal high-gain amplifier, a clamped low-impedance output stage, and a proprietary dynamic offset cancellation technique.

The ALS31000 and A31004 sensor ICs are offered in the LH package style: a SOT-23W style, miniature, low-profile package for surface-mount applications. The package is lead (Pb) free, with 100% matte tin leadframe plating.